Semiconductor devices are sometimes made by insert molding by using thermoplastic resin to seal the semiconductor package made of thermosetting epoxy resin in the housing. However, thermosetting epoxy resin, which is a raw material of the semiconductor package, and thermoplastic resin, which is a raw material of the housing, have different reactions to heat. Thus, the adhesive properties between the two resins become poor after cooling and a gap may form between them. In such a semiconductor device, problems such as a leak or a short may occur due to moisture that comes in from the gap between the package and the housing in certain circumstances.
To prevent this problem, some prior art semiconductor devices have been made using a method different from insert molding. First, as shown in FIG. 3A, a housing 51 having a connector terminal 50 is provided. The connector terminal 50 is preformed by injection molding in a predetermined position of the housing 51. When a semiconductor package 52 is placed in the housing 51, a surface of the package 52 that abuts against the housing 51 has an adhesive agent applied thereon. After the connecting portion 52a of the package 52 is placed in contact with the connector terminal 50, the package 52 is fixed to the housing 51. Next, as shown in FIG. 3B, a space 53 in the housing 51 is filled with a sealant 54 such as liquid epoxy and silicone to seal the package 52.
The above-mentioned manufacturing method, in which the package 52 is sealed with the sealant 54, requires more steps (three) compared to the manufacturing method by using insert molding: a step of making the housing 51 having the connector terminal 50, a step of adhering the package 52 to the housing 51, and a step of filling the housing 51 with the sealant 54. This complicates the manufacturing process as well as increases the manufacturing costs of the semiconductor device.